Archive for June, 2011

by Karen Whitecotton, Curator of Collections

Ever heard of Picric acid? Don’t worry, you’re not alone. Most people have never heard of it, and neither had I until a few days ago. It’s a highly explosive chemical compound (the forerunner to TNT) that has been around for a couple of centuries and has been used primarily as munitions and fireworks.
Picric acid is actually a liquid that over time dries out and crystalizes. When it crystalizes it becomes highly unstable and VERY sensitive to shock and therefore handling it becomes dangerous.It also leaves a distinct bright yellow powdery residue that is easy to spot.

Why on earth would a museum have explosive chemicals, like picric acid in their collections? Simple answer- they don’t know about it. We sure didn’t! Evidently it’s way more common than I would have thought. It wasn’t until a week ago that I learned about picric acid and its explosive properties from reading several emails on the American Association of Museums Registrars’ Listserv (RC-AAM). Someone send out an email inquiry regarding procedures when disposing of hazardous chemicals. A response mentioned the dangers of picric acid -a substance many people have never heard of, but VERY common in early and mid-20th century first aid kits. You see, medical gauze used to be soaked in picric acid to treat, most commonly, burns (interesting tidbit- picric acid gauze was used in the treatment of burn victims from the infamous Hindenburg disaster).

An example of a first aid kit that may have included picric

After that initial email there were email responses DAILY reporting the discovery of picric acid in museum collections around the country and that bomb squads had to be called out to collect and detonate the picric acid infused items. In one case a whole city block was evacuated and a robot was sent in to collect ONE object. In another case an item contained so much picric acid it was enough to blow the museum worker’s hand off! So, as you can see, it’s a very serious hazard to collections and to people!

After reading those emails over the weekend, I thought I would take the cautious route and so I did a database search first thing on Monday morning and discovered 5 objects in our own collection that possibly contained picric acid. These items were all early 20th century first aid kit components: 3 packs of picric acid soaked gauze, 1 box that stored the soaked gauze, and 1 empty tin. After consulting with the museum Deputy Director/Collections Manager, Jeff Briley, I pulled the objects the next day and inspected them. I isolated the 3 packs of gauze and inspected the box. The box had the distinct yellow powdery residue of picric acid on the insides. The metal tin did not show any signs of acid residue, but under Jeff’s advice it was thoroughly swabbed to make sure. We further inspected the associated first aid kit the items came from to make sure there was nothing else of concern. Thankfully there wasn’t. He called his contact at the Oklahoma City Police Department Bomb Squad to ask if they would collect the pieces for disposal. They agreed and said they would be at our facility 7am the next morning with a robot.
Bright and early the next morning we had the police department, fire department, an ambulance, and the bomb squad standing by. At the employee entrance, the bomb squad began staging their maneuver to retrieve the items. Instead of a robot (which I was actually hoping to see – I had Wall-E pictured in my head), they had a guy dressed in a big suit (think the Halo video game suit but twice the size) carrying a long pole. He went in to retrieve the items in a bucket from the fire safe and came back out and carried the bucket around (and down some stairs!) to the containment wagon. They used a small crane to hoist the bucket of items into the containment wagon and then gave the all clear. Whew.

Our disposal of the picric acid infused items went very smoothly thanks to the expertise of the OCPD Bomb Squad. Museums don’t simply dispose of items without very clear reasoning and procedure is always followed to ensure public trust and ethical behavior is maintained. Sometimes there are extreme situations (like hazardous chemicals!) that speed up the disposal process to ensure a safe environment for the collection, the staff, and the public. Hazardous and unstable chemicals are simply not safe to have in museum collections.

This blog brought to you by Karen Whitecotton, Curator of Collections, Oklahoma History Center
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